Balancing act

This new funicular railway system in Mumbai that works on a basic mechnanism, is the first of its kind in the country, writes MONISHA RAO.

By September 2014, Mumbaikars will have the pleasure of riding in India's first funicular railway line. Being built near Kalyan, the railway will ferry devotees to the shrine at the Haji Malang Hill and will significantly reduce travel time from a tedious three hours to just 10-15 minute. Built on an elevated incline along a defined alignment, the railway system has been developed on a 1-km single rail track and a double track of 100 m at the centre. At an average slope of 17°, the elevation difference between the lower and upper station is 230 m.

Working mechanism

This mode of transportation stands out because of its efficient and simple design. A funicular railway works on a basic mechanism: two cars are attached to each other by a cable, which runs through a pulley at the top of the slope. It counter balances the two cars, with one going up and the other going down. In this case, the cars are pulled up by means of an electric drive and a mechanical lift. Elaborating on the working mechanism of the system, ZN Shaikh, General Manager-Execution, Supreme Infrastructure India, says, "The funicular drive will be located behind the upper station. It will consist of an electric-driven capstan, motor, gearbox, couplings, normal brake and an emergency brake mounted on a base frame. This will be permanently anchored to the ground with components fitted on the base frame with fasteners." Currently, the drive elements have been designed for a two-car operation; however, extra designs will be made for an upgrade to four-car operations in the future.

Explaining the system's sustainable factor, he highlights, "With a combination of wheeled cars and tracks, funicular is a sustainable mode of transportation as it does not consume fuel. The power requirement for this system is 400 kw."

The steel girders are 12 m long and each is fabricated from a pair of mild steel (IS2062) parallel beams IPE 600 + 220 + 107.8 kg per m.

The parallel beams are joined by ISMB 150 I beams to form a strong truss. Also, the rails used on the steel girders weigh 125 pound and are of 52 kg per m IU grade. These are clamped on the girders with rail clamps at every 800 mm.

Moreover, the railways have been designed keeping in mind varying dynamic loads. In civil and structural engineering, dynamic or live loads are loads that can change or are applied with motion, such as wind, earthquake, vertical loading, centrifugal force and longitudinal force. M30 grade concrete and TMT bar reinforcement have been used in the RCC pier. "European countries use steel structures to build piers but we have constructed RCC piers for the first time in the world," confirms Shaikh. These pillars also have zero-maintenance cost. "While in India, traditional methods of construction are used to launch girders, we have developed a unique technology by means of a specialised crane on the rough inclined terrain."

Wagon drive

Four fully air-conditioned passenger cabins, each carrying 60 passengers, will move to and fro every 400 seconds to ferry 1,080 passengers per hour, per direction. The cabins on the railway track are connected to opposite ends of a single wire rope, which has six strands with 19 wires each. Moreover, an attached goods cabin to each rake will carry passenger luggage and other goods.

Safe and sound

Safety and security form the most critical element of a funicular system. To ensure a smooth ride, the cabins will have in-built voice and data communication facility along with at least two rail clamp brakes to operate in cases of emergency. Soft brakes have also been provided that ensure a smooth halt during emergencies, leaving no scope for panic. "A number of sensors have been placed at different locations to track movement and prevent accidents," reveals Shaikh.

The cabins have their centre of gravity well centred between the rails. Typically, in a funicular railway, the centre of gravity is never outside 250 mm from the track centreline for a 3-m wide cabin. This ensures reasonably uniform loading on both beams of a girder; hence, a funicular never topples over on the side.

New beginning

The project, which was initially set to commence in 2008, was stuck owing to clearances. However, once the project attained approval from the Forest Ministry, it kick-started its operation in September 2012. The cost of Rs 45 crore at the initial stage has now escalated to Rs 75 crore. "Thirty per cent work of the project is remaining and it will be operational by July-September this year," concludes Shaikh. We can't wait!